What is CVE-2016-9937?

CVE-2016-9937 is a high-severity vulnerability in Digium Asterisk, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.5/10. Published 2016-12-12.

How severe is CVE-2016-9937?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2016-9937 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Digium Asterisk

CVE-2016-9937

An issue was discovered in Asterisk Open Source 13.12.x and 13.13.x before 13.13.1 and 14.x before 14.2.1. If an SDP offer or answer is received with the Opus codec and with the format parameters separated using a space the code responsible for parsing will recursively call itself until it crashes. This occurs as the code does not properly handle spaces separating the parameters. This does NOT require the endpoint to have Opus configured in Asterisk. This also does not require the endpoint to be authenticated. If guest is enabled for chan_sip or anonymous in chan_pjsip an SDP offer or answer is still processed and the crash occurs.

Vulnerability class: Buffer Overflow

Published 2016-12-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.026 (84.8th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 85th percentile — 84.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.026 · newest: 0.026 · change: 0.000

Affected products

Digium Asterisk — versions 13.12, 13.13, 14.0

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

Public proof-of-concept exploits

fkie-cad/nvd-json-data-feeds

References

www.securityfocus.com/bid/94792 (VDB Entry, Third Party Advisory, vdb-entry)
downloads.asterisk.org/pub/security/AST-2016-008-14.diff (Patch, Vendor Advisory)
issues.asterisk.org/jira/browse/ASTERISK-26579 (Patch, Vendor Advisory)
downloads.asterisk.org/pub/security/AST-2016-008.html (Patch, Vendor Advisory)
downloads.asterisk.org/pub/security/AST-2016-008-13.diff (Patch, Vendor Advisory)
www.securitytracker.com/id/1037407 (vdb-entry)

Frequently asked questions

What is CVE-2016-9937?: CVE-2016-9937 is a high-severity vulnerability in Digium Asterisk, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.5/10. Published 2016-12-12.
How severe is CVE-2016-9937?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2016-9937 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.